foo.cc: In function 'int main()':
foo.cc:21:17: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'long long int*' [-Wformat=]
   21 |         scanf("%d",&n);
      |                ~^  ~~
      |                 |  |
      |                 |  long long int*
      |                 int*
      |                %lld
foo.cc:21:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   21 |         scanf("%d",&n);
      |         ~~~~~^~~~~~~~~

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